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LED source for determining optical detector time response at 1.06 microm
1Electromagnetic Technology Division, National Bureau of Standards, Boulder, Colorado 80303, USA.
The Review of Scientific Instruments
|August 1, 1979
Summary
A gallium indium arsenide light emitting diode (LED) was used to create fast optical pulses for testing detector response times. This method generated 2.5-ns pulses and 3-4-ns steps for high-speed optical measurements.
Area of Science:
- Optoelectronics
- Semiconductor Devices
- Photonics
Background:
- Accurate characterization of optical detector time response is crucial for high-speed photonic systems.
- Gallium Indium Arsenide (GaInAs) light-emitting diodes (LEDs) offer potential as fast optical sources.
Purpose of the Study:
- To investigate a GaInAs LED as a source for determining optical detector time response at 1.06 micrometers.
- To generate and characterize impulse and step-shaped waveforms for optical testing.
Main Methods:
- Utilized a charged transmission line switched by an avalanche transistor to drive a GaInAs LED.
- Generated optical pulses with a 2.5-ns full width at half-maximum (FWHM).
- Produced optical steps with a 3-4-ns transition time at repetition rates up to 1 kHz.
Main Results:
- Successfully generated fast impulse and step-shaped optical waveforms using the GaInAs LED setup.
- Achieved high repetition rates up to 1 kHz for the generated optical signals.
- Evaluated the impact of wavelength change during the pulse (chirping) on the measurements.
Conclusions:
- A GaInAs LED driven by an avalanche transistor is a viable source for generating optical waveforms to measure detector time response.
- The generated waveforms are suitable for characterizing high-speed optical detectors.
- Chirping effects were analyzed, providing insights for precise optical measurements.
